Standard O-Ring Cord Cross Sections & Tolerances Class E2
O-Ring cord tolerances are what make or break your seal. Our cord follows Class E2 tolerances, which control how much the cross section can vary from nominal size. That means you get consistent material that installs easier and seals more reliably.
Why this matters to you:
- Cord too large causes over-compression and install issues.
- Cord too small leads to leaks and poor sealing.
- Controlled tolerances keep your process predictable.
Exact Inch | Exact MM | Nominal | Tolerance | Low | High |
|---|---|---|---|---|---|
0.040 | 1.00mm | 1 MM | +/- .010 | 0.029 | 0.049 |
0.062 | 1.60mm | 1/16” Actual | +/- .014 | 0.049 | 0.077 |
0.070 | 1.780mm | 1/16” Nominal | +/- .014 | 0.056 | 0.084 |
0.079 | 2.00mm | 2 MM | +/- .014 | 0.065 | 0.093 |
0.093 | 2.40mm | 3/32” Actual | +/- .014 | 0.079 | 0.107 |
0.098 | 2.50mm | 2.5 MM | +/- .014 | 0.084 | 0.112 |
0.103 | 2.62mm | 3/32” Nominal | +/- .016 | 0.087 | 0.119 |
0.118 | 3.00mm | 3 MM | +/- .016 | 0.102 | 0.134 |
0.125 | 3.175mm | 1/8” Actual | +/- .016 | 0.109 | 0.141 |
0.139 | 3.53mm | 1/8” Nominal | +/- .016 | 0.123 | 0.155 |
0.157 | 4.00mm | 4 MM | +/- .016 | 0.141 | 0.173 |
0.177 | 4.50mm | 4.5 MM | +/- .020 | 0.157 | 0.197 |
0.188 | 4.80mm | 3/16” Actual | +/- .020 | 0.168 | 0.208 |
0.196 | 5.00mm | 5 MM | +/- .020 | 0.176 | 0.216 |
0.210 | 5.33mm | 3/16” Nominal | +/- .020 | 0.19 | 0.23 |
0.218 | 5.50mm | 7/32” | +/- .020 | 0.198 | 0.238 |
0.224 | 5.70mm | 5.7 MM | +/- .020 | 0.204 | 0.244 |
0.236 | 6.00mm | 6 MM | +/- .020 | 0.216 | 0.256 |
0.250 | 6.35mm | 1/4” Actual | +/- .027 | 0.223 | 0.277 |
0.275 | 7.00mm | 1/4” Nom, 7MM | +/- .027 | 0.248 | 0.302 |
0.295 | 7.50mm | 7.5 MM | +/- .027 | 0.268 | 0.322 |
0.313 | 8.00mm | 5/16” | +/- .027 | 0.286 | 0.34 |
0.330 | 8.40mm | 8.4 MM | +/- .027 | 0.303 | 0.357 |
0.354 | 9.00mm | 9 MM | +/- .027 | 0.327 | 0.381 |
0.375 | 9.50mm | 3/8” | +/- .027 | 0.348 | 0.402 |
0.393 | 10mm | 10 MM | +/- .031 | 0.362 | 0.424 |
0.437 | 11mm | 7/16” | +/- .031 | 0.406 | 0.468 |
0.472 | 12mm | 12 MM | +/- .031 | 0.441 | 0.503 |
0.500 | 12.70mm | 1/2” | +/- .031 | 0.469 | 0.531 |
Where this performs
Used in hydraulic and pneumatic systems, fluid handling, food and beverage equipment, chemical processing, and custom vulcanized O-Rings.
Quality you can rely on
Our cord meets ARPM standards, supporting consistent performance and ISO9001:2015 quality practices.
Need tighter tolerance?
If your application requires more control than Class E2, let us know. We can help source or produce cord that fits your exact requirements so you avoid rework and downtime.Need Help Selecting O-Ring Cord?
Whether you need standard stock, metal detectable compounds, FDA materials, or custom manufacturing, our team is ready to help you find the right O-Ring cord for your application.
The O-Ring Store LLC | ISO 9001:2015 Certified | We make getting O-Rings easy.